Ahead of today's sole practice session, the air temperature is 10 degrees C, whilst the track temperature is 19 degrees. It is bright and beautiful, but a little cool. On the other hand it isn't as windy as it was yesterday afternoon.

Lewis Hamilton toped the timesheets in both of yesterday's session however, he missed the final 20 minutes of FP2 with a suspected hydraulics leak. Whilst some fear Mercedes reliability could yet decide the title, the Briton played down their fears and insists he remains fully confident.

Fernando Alonso was third quickest in FP2, ahead of Ricciardo, Massa and Raikkonen.

It was a troubled day for Red Bull with Ricciardo missing much of FP1 with an ERS issue whilst teammate Sebastian Vettel restricted his running in an attempt to 'save' his all-new powerplant for the remaining races. Incidentally, the German will take part in qualifying today but, in lieu of the fact that he has to start from the pitlane due to that power unit change, will only take part in Q1.

McLaren looked strong in FP1 but was not so impressive in the afternoon once the option (soft) tyres came into play. Consequently, Red Bull and Williams appear to be the biggest threat - if that's the right word - to Mercedes this weekend.

However, all this pales into significance in the wake of claims late yesterday that three teams - Force India, Sauber and Lotus - are considering boycotting tomorrow's race in reaction to the current state of the sport in terms of the divide between the haves and have-nots, a divide forced back into the spotlight by the failures of Caterham and Marussia, both of which are missing from this weekend's event.

The lights go green and Bottas leads Maldonado, Raikkonen and Grosjean out of the pits and up the hill to T1. Surprisingly, Vettel is another early riser.

Magnussen posts the first time of the day, the Dane stopping the clock at 1:48.261. Next time around the McLaren driver improves with a 41.567, whilst Vergne goes second with a 43.084.

As Gutierrez goes third (44.482), ahead of Button and Perez, all 18 drivers have been out, if only for an installation lap.

Magnussen and Button both improve to make it a McLaren 1-2, but moments late a 41.159 from Hulkenberg splits the Woking duo.

Sutil runs wide at T12, as the cameras pick up three 'sleeping policemen' that have been installed on the outside of the final corner overnight.

"Cold temperatures mean that tyres take longer to reach their ideal working range," tweets Pirelli. "So drivers do long runs to get heat into them."

A 39.820 sees Massa go quickest, as mechanics continue to work on Rosberg's car.

Drivers continue to fall foul of T12, Perez being the latest.

Bottas looks set to make it a Williams 1-2 until Kvyat bangs in a 40.526 to take the second spot.

As reported, Frank Williams is not here this weekend, the team founder is in hospital in England with a "pressure sore".

Ricciardo posts 40.073 to go second as teammate Vettel leaves the Red Bull garage. The German is the first driver to switch to the option rubber.

Ricciardo improves with a 39.693 to go quickest with Bottas slipping into second moments later, the Finn having been quickest of all in the first two sectors.

"There's something at my elbow which is disturbing me," complains Kvyat, the Russian currently fourth fastest (40.514).

Alonso posts 39.915 to go fourth and demote Kvyat.

Twenty-five minutes into the session, all but Rosberg, Vettel and Hamilton have posted times.

Vettel, who like yesterday appears to be focussing on high fuel running on options, posts 45.529 to go 16th. The German faces a long afternoon tomorrow.

Hamilton heads out for a single lap before heading back to the pits, as he returns teammate Rosberg heads down the pitlane.

At half-time, both Mercedes drivers are on track, circulating almost in tandem.